It was contended in a previous communication that all valleys have been formed by sub-aërial agencies alone, and that the disintegrated materials, being carried seaward by the rivers traversing them, have accumulated to immense thicknesses in what had been formerly a continuation of these valleys, and have, by their weight, caused progressive subsidence, and so have formed bays and to some extent deltas at and near their mouths.

The Coal-measures of the Brown Clee are of themselves extremely insignificant and unimportant. The total area is limited, and the thickness of the coals would not have entitled them to be considered of commercial value, if it were not for the fact, that from its elevated position it is placed well above the reach of water, and hence the great difficulties which beset early mining operations in freeing the mines from water did not affect the coal-mines of the Brown Clee; consequently, in those times they were worked to advantage, but there is very little coal remaining to be won. They have, however, a value to the geologist, as indicative of the much wider range of the Coalbrookdale Coal-measures than is shown by its present boundary, for there is an unmistakable analogy between both deposits, to which, we shall presently refer.

Having read Mr. Price's note and description of Rostellaria maxima in last month's Number (p. 97, Pl. VI.), I venture to express my regret that so doubtful a species should be published with the apparent authority of the GeologicalMagazine to confirm it; especially as Mr. Wiltshire (than whom there is no one better acquainted with English Cretaceous Mollusca) is of opinion that it is only a giant form of Rostellaria carinata. The description given by Mr. Price would equally apply to the ordinary form of R. carinata which occurs in the same bed, and, save in size, exactly resembles it. The most distinctive portion of the shell, the wing, is unfortunately not preserved. The examples of Rostellaria carinata found in this bed, I may remark, always differ slightly in form, being broader and more obtuse (they are also usually more crushed and imperfect) than those from the lower beds. I am fully; convinced that, if size alone is sufficient ground to justify the formation of new species, we shall speedily find the present confusion of names in the Gault fauna more hopelessly involved and more impossible to unravel than ever. What, for instance, would be the result of the adoption of such a basis of nomenclature for the Cephalopoda from the same formation ?

Two remarkable geological features present themselves in this little valley: one, the occurrence of the Upper Coal Measures of Bewdley, together with the well-known Spirorbis Limestone; the other, that of the Bone-bed, succeeded by the no less interesting Passage-beds, forming connecting links between the Old Red, Sandstone and Upper Ludlow Limestone. The order in which these occur, taking both banks of the brook, appears to be this.

In the December Number of the GeologicalMagazine there is an abstract of a most interesting paper published in the “Jahrbuch für Mineralogie”, etc., of Leonhard and Geinitz, by C. W. C. Fuchs, entitled, “The Geological, Microscopical, and Chemical Examination of the old Sedimentary Formations in the French Pyrenees, with especial reference to the Metamorphosis of these and other old Rocks”. In this paper attention is called to the manner in which the degree of metamorphism of clay-schists and other rocks is sometimes indicated by the formation and gradual development of certain minerals, Andalusite and Chiastolite being those specially mentioned.

In a paper of mine on. “The Glacial Phenomena of the Yorkshire Uplands,” read before the Geological Society of London in the spring of 1872, compared the valley of the Wye in Derbyshire to those of the Aire and Calder in Yorkshire. This was a mistake: the Wye rises on the west side of the geological axis and crosses the anticlinal; but its valley does not cross the physical axis, which is nowhere broken through, as in the cases of the Aire and Calder. The lowest part of the watershed at the head of the Wye basin is at Doveholes, near Chapel-en-le-Frith. I made some observations by aneroid to ascertain the height of this point. The watershed south of Doveholes was by aneroid 1300 feet above the sea, and that north of Doveholes 1250 feet; but as the glass was falling on the day of my visit, these heights are too great by somewhat less than 75 feet, the total amount of the fall. This will make them between 1225 and 1300, and between 1175 and 1250 feet respectively. On another occasion I estimated the height of the watershed north of Doveholes at 1200 feet, and that on the Peak Forest Railway at 1175 feet. A couple of miles to the N.N.E. I found Sparrow Pit to be 1350 feet above the sea, and Perrydale 1200; the plateau above Perrydale 1350; the watershed under Mam Tor 1500; and the lowest point of Rushup Edge 1525 feet above the sea.

The following remarks were written for the Settle Caves Exploration Committee in the spring of 1871. They were subsequently submitted to the British Association in 1872, and are, with additions embodying the result of the latest explorations, offered to the scientific public. First, I propose briefly to describe the beds with which we have become acquainted in the course of the explorations, their apparent range and superposition. Secondly, I will endeavour to show to what natural causes they probably owe their origin.

In accordance with our plan, we now proceed to sketch the history of the Lower Palæozoic rocks in North America. While European geologists were carrying out the researches which have been described in the first and second parts of this paper, American investigators were not idle. The geological studies of Eaton led the way to a systematic survey of the State of New York, the results of which have been the basis of most of the subsequent geological work in eastern North America, and which was begun by legislative enactment in 1836.

2. Middle and Lower Cambrian.—Investigations in continental Europe were, meanwhile, preparing the way for a new chapter in the history of the Lower Palæozoic rocks. A series of sedimentary beds in Sweden and Norway had long been known to abound in singular petrifactions, some of which had been examined by Linnæus, who gave to them the name of Entomolithi. They were also studied and described by Wahlenberg and by Brongniart, the latter of whom, from two varieties of the Entomolithus paradoxus, Linn., established in 1822 two genera, Paradoxides and Agnostus.

It has been argued by some that the seas were anciently cooler than at the present day, and that thence certain ulterior effects might be assumed. Without treating of the supposed effects, I wish to state that the premiss itself seems to me inconsistent with what, geologically viewed, appears to be the order of transition through which our planet has passed in its successive changes. My own unprofessional view, founded upon grounds generally admitted, has been that, from a temperature originally much higher, the oceans had gradually cooled down under adequate influences to the mean temperatures which they now maintain under the permanent climatic conditions of the globe; and indeed that the peculiar condition distinguished by geologists as the “Glacial Period” was but the effect of the rapid condensation of the vapours arising during the longcontinued process of cooling, under a great and sudden organic change.

In former papers I have described central Lancashire as capable of division into three plains of different elevations. The lowest being often beneath high-water mark, and always below the 25-foot Ordnance contour; the second ranging from 25 and 50 feet to 500 feet above the sea, terminating at the foot of the steep escarpment at the western edge of the Lancashire and Yorkshire moorlands forming the Pendle portion of the Pennine chain, with an average elevation of 1200 feet. Both the lower plains are much covered with drift, and the rock-surface at the sea-coast is often 50 feet below low-water mark, steadily rising in one gradual inclined plain, eastwards, or towards the Fells.

In the fourth part of my Monograph on the Merostomata, published in last year’s volume of the Palæontographical Society’s annual issue, I drew attention to two very singular fossil remains which had been somewhat doubtfully referred by Mr. J. W. Salter to the genus Eurypterus. A portion, at least, of the remains referred by him to Eurypterus? mammatus are really plant-remains (as shown by Mr. Carruthers, op. cit., p. 168), whilst the remainder must, for the present, be classed with M. Jordan’s Arthropleura armatu, from the Coal-measures of Saarbruck, Rhenish Prussia, a very anomalous Crustacean (if it be a Crustacean at all, which I greatly doubt), but which is certainly not a Eurypterus.

The Upper Greensand of Cambridge occurs as a thin but very important bed, covering the eroded surface of the Gault, and blending upwards into the overlying Chalk-marl. It consists essentially of Chalk-marl, saturated with green grains of Glauconite, and crowded with a variety of fossils. The fossils in great part derive their origin from the Gault, out of which they have been concentrated by a natural process of levigation. At the time when the Gault sea was shallowing to its close, its submarine shores became eroded by a cold current flowing from the north, which bore away its lighter sedimentary clay, and left its imbedded fossils behind, to be subsequently rolled into the sublittoral deposit of the Upper Greensand. Thus it happens that in our neighbourhood the uppermost beds of the Gault are not to be found, and their only representative is this mere pebble-bed at the base of the Chalk. The rich fauna in our formation thus collected ready to the hand of the Palæontologist has been well worked out in its higher developments by Mr. Barret, Mr. Seeley, and various other observers. Of the Protista and Cœlenterata, however, some departments have been left all but untouched; and it is to the Sponges of the latter and the Foraminifera of the former that my paper refers. The Foraminifera occur abundantly, and in a rich variety, which seems to anticipate their more luxuriant appearance in the succeeding Chalk. The Vitrea perforata are represented by large forms of Bulimina, Textularia, and Orthocerina, which mimic truly arenaceous foraminifera by imbedding the siliceous and volcanic sand of the formation in their tests.

My thanks are due to Mr. Tiddeman, for his reply to the letter from me, which appeared in your February Number. I may perhaps be allowed to add a few words more upon the subjects under discussion.

The district known as Cannock Chase is, at the present moment, the scene of a series of extensive mining operations which, if even moderately successful, will open up a very considerable area of valuable coal-seams, computed at not less than 200,000,000 tons, and push outwards a distance of upwards of five miles the northern apex of the South Staffordshire Coal-field. This apex, as is well known, now rests on Brereton, where the Coal-measures are thrown down on the east by a fault of considerable range and influence, and on the west they are overlapped unconformably by Bunter conglomerates. From this point the conglomerates are continued in a broad unbroken tract, over the Chase to within about four miles of the town of Stafford, up to which point the mining investigations, to which I have alluded, will be extended.

In the following communication I intend to give a very brief outline of some of the chief results of my investigations among British Graptolites in those departments of inquiry which are more especially connected with consideratious of classification. I shall content myself with offering a concise statement of the main conclusions at which I have arrived, reserving all detail to the future, when I hope to adduce decisive evidence in support of the views here advanced. The special subjects to be noticed in this place are—the development, structure, classification, and geological distribution of that section of the Rhabdo-phora in which the complete polypary can be proved to be composed of one or more polyparies essentially similar to that in the unilateral and uniserial forms to which the name Graptolites (Graptolithus) is commonly applied. Those Rhabdophora supposed to be similar in structure to the genus Retiolites will be considered in conjunction, but no pretension is made to anything like the same certainty in this section.

Crystallographic, like all other formulæ, are simply short-hand methods of describing that which could otherwise only be rendered intelligible by the expenditure of many words, and, in type, by considerable waste of space. Anything, therefore, which tends to simplify and contract formulæ, without diminishing the amount of information which they convey, must necessarily be advantageous. The different systems of notation used at the present time by eminent crystallographers render the comprehension, of their formulæ somewhat difficult to the student; and it would doubtless be productive of much satisfaction if a universal system of crystallographic notation could be adopted.

These Foraminifera were obtained from fifteen zones of the Jurassic strata, between Solothurn, in Switzerland, and the Eichberg, in Baden: three Liassic zones (Black or Lower Jura); six in the Brown or Middle Jura; and six in the White or Upper Jura; beginning with the Turneri-zone of the Lower Lias, and ending with the Pteraspis-zone of Schaffhausen. The Numismalis marl, Amalthei-clay, Murchisonæ-bed, Discoidei-marl, Crenularis-bed, the Coral-limestone, and the Virgulian stage yielded few or no traces of Foraminifera.